Now that the elections are over and the footy has quitened down I have an astronomical question. Iam having a few problems with a dew heater for my secondary mirror in my 10" dob. Astrosystems advise they can't supply the units due to the mirror size being 2.27". They have only 2.13" and 2.6". Is it feasible to change the mirror to a smaller or larger one, and if so would their be any draw backs. Vince